Boiler



F. W. BAKER April 30, 1929.

BOILER Filed Nov. 15, 1925 JUL I? IN? 022 fledcra, W-

Patented Apr. 30, 1929.

semen. l

. Application flied Rdvember 15,,1aee. swarms use;

My invention relates to boilers and an object of the invention is toprovide a boiler structure including a firebox composed of a pluralityof water legs which are bowed or curved to present concavesurfaces,,towards each other for thepurposc of providing staylesswater-legs which may be thoroughly cleaned, andjwhich have a sustainedcapacity.

A further object of" the invention is to provide a return tube boiler inwhichthe drum is placed as a unit upon a unit fireboxstructure, and onein which the drum shell is extended rearwardly beyondthe backtubesheetto forfnthe rear smoke box] and top of the combustion chamber.

Another object of the invention is to rovide in a boiler structure, afirebox of our separate chambers, each of which contains water and whichare connected with the drum, at the top of the various water legs orchambers, and the bottom of the drum, the return from the radiatorsbeing heated at the bottom of the various chambers, thereby permittingthe preheating of the water prior to its entrance into the drum.

Other objects of the invention will appear in the following detaildescription, and in the accompanying drawings wherein:

Figure 1 is a longitudinal section through the boiler.

Figure 2 is a cross sectionthrough the g by the reference numeral 24,for COIltitllllXlgf boiler.

Referring more particularly to the drawings, 1 indicates the drum of areturn tube boiler of approved type, which has a front tube plate 2,rear tube plate 3 and body shell 4. Itwill be noted by particularreference to Figure 1 of the drawings, that the upper portion 5 of thebody shell is extended rearwardly beyond the rear tube plate 3 formingthe rear smoke-box and top of the combustion chamber and thatthe tubes1' are all of equal length. The drum 1 has a plurality of angle irons 6riveted or welded thereto, which angle irons are in turn bolted orsuitably attached to the upper edges of the walls of the fire-box arcand are positioned with their concave sur-, faces fac ng. as clearlyshown in Figure 2,

of the drawings, toprovide sriflicient strength without requiring the iuse of stay bolts, "such, as ord nari y used with. flat plates,ent-liaise proiriding a chamber within. itheiplateslO and i 11 for?"containing wateniwliichis 1 preheated and which passesfromthe upperedges ofthe sides 8 and 9 through curved pipes 12linto the drum. Thepipes 112 commanicute with the along the inner side ofthe drumto permitthe introduction of the water intolthe drum at its lowest point. a a

water ll egs orsidesQSandQ at the'ir highest .1)O1Ill S,.a11(l extendinto *the drum curving The front 14 of the fire-box structure is i madeup of spaced flat plates 15 and 16, which are spaced bysuitabledistancepiecesand' stays 22. The fire box door front is indicated by thereference numeral 22'. Theplates and 21 like the plates 15 and 16, ofthe front, are spaced to provide a chamber, as indicated water andthesec'hambers 18 and24 have outlet communication with the drum throughsuitable pipes, one of which i is indicated at 25' and shown in Fi -ure1 at the upper? her 24. :The cham-= most part of the cham bers 18 and 24and the chamberswithin the plateslO and 11' have inletconnect-ions attheir lowermost points" through suitable pipes 25. i A drain pipe 26 isprovided and communicates with the lowermostportion of the drum and hasbranch pipes 26 which communicate with the lowermost portion of thewater chambers in the walls of the fire box and this drain, pipe may beprovided with a suitable valve as indicated by the .referencenumeral'26". The combustion chainber projects.rearwardly beyond the rearend of the drum 1 and permit-sthe double passage. of the products ofcombustion therethrough prior to its delivery to the stack29. From theforegoing description, taken 3 in connection with the accompanyingdrawings, it will be apparent .that'a boiler'structure has been providedwherein, the products of combustion will be guided rearwardly into thecombustion chamber, and upwardly therefrom through the drum, and thatthe heating qualities of the products of combustion will be utilizedtwice for the heating of the water, first, by heating the Water in thewater legs and second, by heating the water in the drum, as the productsof combustion pass through the tubes thereof. The top of the combustionchamber is fitted with fire-brick as shown at 30 or by a horizontallydisposed perforated baffle plate, which may be used instead of thebricks, if it is desired. By the fire bricks or bafiie plate beingdisposed as shown, the products of combustion are deflected through thelower group oftubes as shown in Figure 1 and then through the uppergroup to the stack 29, thetravel of the products being indicated by thearrow in Figure 1.

It is, of course, to beunderstood, that the invention may be constructedin various other manners and the parts associated in differentrelations, and therefore, I do not desire to be limited in any manner,except, as set forth in the claims hereunto appended.

WVhat I claim is:

1. In a fire box structure for a boiler, a wall comprising, twooutwardly curved, oppositely disposed plates cooperating to provide awater chamber.

2. In a boiler comprising a drum and a fire box, outwardly curved platescooperatively associated to provide chambers forming the side walls ofthe fire box, and pipes having communication with the highest point ofthe chambers and the lowest point in the drum.

3. In a boiler comprising a drum and a the box, outwardly curved platescooperatively associated to provide chambers forming the side walls ofthe tire box, and means of communication between the chambers and thedrum.

In testimony whereof, I have hereunto aifixed my signature. l

FREDERIC V. BAKER.

